Brendan Kevin Patrick Scaife FTCD, MRIA, Boyle Laureate[1] (/skeɪf/; born 19 May 1928), is an Irish academic engineer and physicist who carried out pioneering work on the theory of dielectrics.
Scaife showed that in a linear system the decay function is directly proportional to the autocorrelation function of the corresponding fluctuating macroscopic variable, and proved how the spectral density of the dipole moment fluctuations of a dielectric body could be calculated from the frequency dependence of the complex permittivity,
At Queen Mary College there was a high-voltage laboratory run by Hans Tropper, whose lectures on electromagnetic theory inspired Scaife.
After graduation, he began research into the properties of insulating materials under Tropper's direction.
Scaife was the first scientist to successfully measure the complex permittivity of a number of polar liquids such as eugenol, glycerol and water as a function of pressure up to 12 kbar.
Up to that time, Chan and Danforth working in Bridgman's laboratory in the US, had measured essentially the equilibrium relative permittivity ε(ω) of a number of liquids.
A three terminal transformer coupled ratio arm bridge based on Blumlein's invention prior to the War had been constructed at Queen Mary by an Indian student S. Sharan for his PhD work.
After completing this work and a brief period of employment with GEC in Wembley, he returned with his Irish parents to Ireland where he remained for the rest of his career in spite of many offers from abroad.
His interest in the theory of dielectrics led to a collaboration with Herbert Fröhlich at the University of Liverpool, where he was a regular visitor in the 1950s and 1960s.
of dipolar substances had been developed by Kirkwood (1939) and Fröhlich (1948), who built on the pioneering work of Debye (1913) and Onsager (1936).
It was hoped that the results of his 1959 report could be used to generalise the work of Onsager, Kirkwood and Fröhlich and to obtain a theory for the frequency dependence of the complex permittivity
Sack's work was based on the Fokker Planck equation governing the temporal evolution of the orientational distribution for molecules.
In an attempt to clarify the physical aspects of the problem, Scaife derived Sack's results by starting from the stochastic Langevin equation (1908) of molecular rotational brownian motion.
His work on the plane rotator, and also for the sphere, was published for the first time in 1971; it was published in collaboration with John T. Lewis[2] and James Robert McConnell[3] (also a Boyle Laureate) in Proceedings of the Royal Irish Academy A, 76 (1976) 43 (It is for this paper that he appears in Famous Trails to Paul Erdős).
are the real and imaginary co-ordinates of the function which is directly proportional to the complex polarizability of a macroscopic sphere of unit radius.
Coffey, he explored the extension of Onsager's theory to take account of high field effects on the polarisation of dipolar materials.
With research students K. Raji, J. C. Fisher, K. V. Kamath and V. J. Rossiter he carried out experimental studies of the equilibrium permittivity of alkali halides when subjected to high pressures.
Later Garrett Scaife took a keen interest in designing and automating the high-pressure equipment and establishing the dielectric measuring techniques, and devoted a good part of his career studying the dielectric properties of liquids and liquid crystals under high pressures.
In one of the papers published in the Philosophical Transactions of the Royal Society of London, 269 (1971) 217, they showed that the complicated transient voltage and current behaviour observed in liquids under irradiation can be explained by a simple model of the motion of space charge in a dielectric medium.
[6] He also explored the dispersion of the frequency dependent magnetic susceptibility of these fluids, developing the necessary underlying theoretical understanding.
Besides his interest in dielectrics and magnetic fluids, he has made contributions to telecommunications, mathematical methods in signal processing and to the history of science and technology.
Sean Swords' doctoral thesis (under Scaife's supervision) was published as Vol.6 in the IEE History of Technology Series.
Scaife together with another former student, J. K. Vij, developed a new theory of absorbance for the electromagnetic spectrum.
In 1972 he was appointed to a chair of engineering science and in the same year was elected to the Royal Irish Academy.
In 1986 he was elected to a Personal Chair in Electromagnetism in recognition of his international reputation in the field of Dielectrics.
Scaife Prize[12] to undergraduate students in electronic and electrical engineering in his honour.